mesh-lab/test/diagram.test.ts

import { test } from "node:test";
import assert from "node:assert/strict";
import { loadScenario } from "../src/declaration/parse.ts";
import { diagramFromDeclaration } from "../src/diagram/from-declaration.ts";
import { toDrawio } from "../src/diagram/drawio.ts";

/**
 * A generated diagram that will not open is worse than no diagram — it looks like a
 * deliverable and is not one. The first version was unparseable because HTML labels were
 * concatenated raw into an XML attribute, so these assert the file itself.
 */

function parseCells(xml: string): { id: string; vertex: boolean; edge: boolean; source?: string; target?: string }[] {
  const cells: ReturnType<typeof parseCells> = [];
  // <object> wrappers carry the id for any cell with a tooltip; the mxCell inside has none.
  for (const match of xml.matchAll(/<object ([^>]*?)>/g)) {
    const id = /id="([^"]*)"/.exec(match[1] ?? "")?.[1];
    if (id) cells.push({ id, vertex: true, edge: false });
  }
  for (const match of xml.matchAll(/<mxCell ([^>]*?)(?:\/>|>)/g)) {
    const attrs = match[1] ?? "";
    const get = (name: string) => new RegExp(`${name}="([^"]*)"`).exec(attrs)?.[1];
    const id = get("id");
    if (!id) continue;
    const entry: (typeof cells)[number] = {
      id,
      vertex: get("vertex") === "1",
      edge: get("edge") === "1",
    };
    const source = get("source");
    const target = get("target");
    if (source) entry.source = source;
    if (target) entry.target = target;
    cells.push(entry);
  }
  return cells;
}

const scenario = loadScenario("scenarios/the-ordinary-shape.yml");
const xml = toDrawio(diagramFromDeclaration(scenario));

test("the file is well-formed XML — raw markup in an attribute is not", () => {
  // No unescaped angle bracket may appear inside a value="..." attribute.
  for (const match of xml.matchAll(/(?:value|label|tooltip)="([^"]*)"/g)) {
    assert.doesNotMatch(match[1] ?? "", /[<>]/, "a label carries raw markup into an attribute");
  }
  assert.match(xml, /^<mxfile /);
  assert.match(xml, /<\/mxfile>\s*$/);
});

test("every edge connects two cells that exist", () => {
  const cells = parseCells(xml);
  const ids = new Set(cells.map((c) => c.id));
  for (const edge of cells.filter((c) => c.edge)) {
    assert.ok(ids.has(edge.source ?? ""), `edge ${edge.id} has no source`);
    assert.ok(ids.has(edge.target ?? ""), `edge ${edge.id} has no target`);
  }
});

test("the diagram draws the implicit routers, not only what is written down", () => {
  // A scenario never names its gateways. A picture that showed only declared machines
  // would omit every node carrying NAT, forwarding and expiry.
  const diagram = diagramFromDeclaration(scenario);
  assert.ok(diagram.machines.some((m) => m.kind === "router"), "no router drawn");
  assert.ok(diagram.machines.some((m) => m.kind === "transit"), "no transit drawn");
});

test("a router's badges say what the declaration decided", () => {
  const diagram = diagramFromDeclaration(scenario);
  const unforwardable = diagram.machines.find((m) => m.notes.some((n) => n.includes("NOT forwardable")));
  assert.ok(unforwardable, "the unforwardable gateway is not marked as such");
  assert.ok(
    diagram.machines.some((m) => m.notes.some((n) => n.includes("mappings expire"))),
    "a declared mapping expiry is not shown",
  );
});

test("a metadata fact becomes a badge, and absence of the fact does not", () => {
  // The point of the badges: the properties worth seeing are the ones with no visual
  // consequence. A translated address looks exactly like an untranslated one.
  for (const tip of ["translates v4", "no port forwarding", "mappings expire"]) {
    assert.ok(xml.includes(tip), `no badge explains '${tip}'`);
  }
  // A gateway that does not translate gets no mark, rather than a struck-through one.
  assert.doesNotMatch(xml, /label="N"[^>]*tooltip="[^"]*no NAT/);
});

test("every badge says in words what its letter means", () => {
  // A one-letter code with no tooltip is a private language. Each badge is wrapped in an
  // <object>, which is the only place draw.io reads a tooltip from.
  const badges = [...xml.matchAll(/<object [^>]*label="([A-Z▶■]{1,2})"[^>]*tooltip="([^"]*)"/g)];
  assert.ok(badges.length > 0, "no badges rendered at all");
  for (const [, code, tip] of badges) {
    assert.ok((tip ?? "").length > 10, `badge ${code} has no explanation`);
  }
});

test("no two cells share an id — a machine may be named after a gateway", () => {
  const ids = parseCells(xml).map((c) => c.id);
  assert.equal(new Set(ids).size, ids.length, "duplicate cell id");
});

test("segments are ordered public first, then by depth behind them", () => {
  const diagram = diagramFromDeclaration(scenario);
  const publicDepths = diagram.segments.filter((s) => s.kind === "public").map((s) => s.depth);
  assert.deepEqual([...new Set(publicDepths)], [0], "a public segment should be at depth 0");
  const home = diagram.segments.find((s) => s.name === "home");
  assert.equal(home?.depth, 1, "a segment behind one gateway is at depth 1");
});

test("a declared address appears on the machine that holds it", () => {
  assert.match(xml, /192\.168\.1\.135/);
  assert.match(xml, /198\.51\.100\.7/);
});

test("every shape names a stencil that exists", () => {
  // A style naming a stencil draw.io does not have renders as an empty box — no error, no
  // warning, just a missing picture. Checked against the names in draw.io's own
  // stencils/networks.xml, which is where mxgraph.networks.* is defined.
  const KNOWN = new Set([
    "mxgraph.networks.server",
    "mxgraph.networks.router",
    "mxgraph.networks.cloud",
    "mxgraph.networks.firewall",
    "mxgraph.networks.switch",
    "mxgraph.networks.pc",
    "mxgraph.networks.laptop",
    "mxgraph.networks.storage",
    "mxgraph.networks.modem",
    "mxgraph.networks.mainframe",
  ]);
  const used = new Set([...xml.matchAll(/shape=([a-z0-9_.]+)/g)].map((m) => m[1] as string));
  assert.ok(used.size > 0, "no stencil shapes used at all");
  for (const shape of used) {
    assert.ok(KNOWN.has(shape), `'${shape}' is not a stencil draw.io ships`);
  }
});

test("a resource's shape is fixed by kind, and never varies with its metadata", () => {
  // The split the whole design rests on: shape says what a thing is, badges say what is
  // true about it. A gateway that stops translating must still look like a gateway.
  const routers = [...xml.matchAll(/shape=mxgraph\.networks\.router/g)].length;
  const diagram = diagramFromDeclaration(scenario);
  assert.equal(routers, diagram.machines.filter((m) => m.kind === "router").length);
  assert.equal(
    [...xml.matchAll(/shape=mxgraph\.networks\.server/g)].length,
    diagram.machines.filter((m) => m.kind === "machine").length,
  );
});